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Comment Apple (Score 1) 118

Any other company would be cutting the price so they didn't make as much profit per unit but could shift units.

But Apple just stop producing as many units and retain the same price (which is going to be at least 50% profit, probably more like 80-90%, given Apple's history here).

This product's gonna be dead in 2 years, and they likely won't make another.

Comment Re:Titan or Bust! (Score 1) 69

I think your confusion stems from analogy to baking clay or ceramics. But what's happening there is sintering. You have extremely fine grains, and you're leading certain crystals to soften and merge as a "glue" between grains, so that the grains stay together.

While sintering is important in the formation of some types of sedimentary rock, this has nothing whatsoever to do with igneous rock. It's already as "together" as it's ever going to be when it a lava flow solidifies. The only thing its grains can ever become is "less together".

And even ignoring that, by definition, you're not going to be sintering something that formed at Venus temperatures, by exposing them to Venus temperatures. The process of sintering requires a radical change in conditions.

Comment Re:Titan or Bust! (Score 1) 69

We are not capable of building anything that can withstand the surface pressures and temperatures for very long

The Venera probes have likely still not experienced any sort of crushing. You seem to be confused about how pressure works. If you don't exert stress pass the yield point of a material, the length of time until something crushes is "infinite". Which is why, say, almost all rocks buried in Earth's crust are able to remain intact over millions to billions of years.

You build of a thickness that the yield point at the design temperature is well above the amount of pressure-induced stress. The Venera probes' pressure vessels - uninsulated - hit surface temperature quite quickly (indeed, mostly during the descent itself). This did not make them crush, because their engineers were not morons who didn't do the math first when determining the probes' required specs.

All probes are designed to their environment. There is nothing magical about the nominal 92 MPa / 464 C of Venus's mean surface (note: this is for the mean surface; the highlands are significantly lower pressure and significantly cooler) that makes it impossible while, say, designing a lander to operate in the cryogenic conditions of Titan or whatnot is easy. This is 1960s tech. Steel alloys usually melt at up to 1400 C or so. Titanium at 1670 C. Tungsten at 3422 C. Some ceramics don't decompose until nearly 4000C. And pressure increases melting points. Now, it's not just the melting point that matters - higher temperatures mean lower yield strengths, so you have to design with the high temperature yield strengths in mind, not room temperature ones. But the simple fact is that various alloys and compounds can operate fine at WAY above Venus surface temperatures. It's not even close. The pressure vessel needed for the Venera probes was just a thin skin.

And to repeat: if the stress doesn't don't go above the yield point, the time to crushing is infinite. Same as any other pressure vessel, from aerosol cans to propane tanks to spacecraft in space (-1 atm).

And I'll repeat: with the same trivially-simple 1960s-tech method as the Venera probes, you can get surface residence times of a couple hours. With heat pumps, indefinitely. And "Baron_Yam at Slashdot" isn't going to override the actual NASA researchers who have worked on this topic.

The rock of Venus is dry-baked to incredible strength

The fact that you think that rock can be "baked to incredible strength" is itself a boggling concept. Not even accounting for the fact that we can literally see sand and gravel in the Venera images, and the Venera probes literally took surface samples. We can see dunes from orbit on radar. Just the very concept that you think that if you heat rock to a couple hundred celsius that makes it super hard, when the rock formed from vastly-hotter lava. Heat makes rock softer, not harder. And subliming away compounds or chemically eroding rocks makes them weaker, not stronger.

From a bulk composition perspective, Venus's surface is mostly just basalt - though there's some probable rhyolitic flows in places, possibly some unusual flows rare or nonexistent on Earth, and there's speculation that some of the highlands may contain residual granitic continental crust. The specific details of said rocks can be quite interesting, but from a bulk perspective, it's like oceanic crust. We know this because we've literally sampled it..

Comment Re:Titan or Bust! (Score 1) 69

That's a lot of text to not mention the need to build floating cities and not die on the surface, which even NASA has not been able to do for more than a few minutes

In case you didn't notice, NASA also hasn't built cities on Mars either, despite spending two orders of magnitude more money on it in recent decades than Venus.

Anyway, we don't need the most Earthlike atmosphere, we need to survive in an environment where we actually know how to do that.

Which requires creating Earthlike conditions. Starting with reasonably Earthlike conditions certainly is a good start.

Comment Re:We should be using the excess electricity (Score 1) 305

To drive desalinization plants and solve the water crisis in the Southwest.

While desalination is a great use of excess power, this is not an easy thing to do because the places where the water is needed are inland. Obviously it doesn't make sense to pump desalinated water 180 miles uphill from the Gulf of California to Phoenix, what you really want to do is to use desalinated water at the places nearer the coast so they can stop relying on the river water that comes from the mountain west, so the southwest can use more of it (and so the mountain west can keep more of it for our own use). But while you could get some benefit from getting the coastal cities using desalinated water, their use actually isn't that significant. The bulk of the water goes to California farmlands, and those are in a belt 70-100 miles from the coasts, and there are mountains in between. Not terribly tall ones, but enough to make pumping the water challenging.

None of this means what you say isn't a good idea, but it does mean that a lot of infrastructure has to be built to make it work. Big coastal desalination plants, big pipelines from those plants, fed by big pumps, and either additional reservoirs or perhaps large tanks in the mountains to buffer the water supply -- though only after peak supply rises to the point that it exceeds demand. Heh. That's exactly the same situation as with intermittent, renewable power, just shifted to water. Water is a lot easier to store, of course, but you still have to build the infrastructure to store it.

So, this is a good idea, but it's an idea that will take years, probably a decade, to realize... and we have excess power now. Of course, starting by tackling the easier problem of using desalinated water in the coastal cities while the infrastructure is built out and scaled up makes sense.

Comment Re:Bundling fixed costs into per-KWH ... (Score 1) 305

The entire problem stems from the fact that the per-KWH charge is actually some gross amalgam of actual cost to deliver an additional KWH plus fixed costs like (in theory anyway) keeping the grid maintained.

Yep. This, like many problems associated with regulated utilities, is one where the right answer is also pretty simple: Just make the prices reflect the costs, then let the market sort it out. But the "just" in that statement belies the political challenges of making such changes.

Comment Re:Googlers are already doing unethical work (Score 1) 220

Googlers are supporting a corporation that's violating privacy

You assume. You should consider that people with an inside view who see what data is actually collected, how it's secured and managed and how it's used, may have a very different perspective on that. I mean, without an internal view you understandably have to assume the worst, but they (we) don't.

Speaking for myself, I very few concerns about Google's privacy violations today. But with respect to the future, you and I are in the same boat, neither of us can know what a future version of the company might do. And on that score I suspect you and I would find ourselves in strong agreement on the potential for serious harm. Where we might differ again is that I see the work being done to limit Google's access to user data so I'm cautiously optimistic that before all vestiges of the old corporate culture are lost and the bean counters take over completely, Google will largely have ceased collecting and using data for advertising and what remains will be easy to limit and make safe.

Comment Re:Not true (Score 1) 154

Re: your subject "Not true", the data doesn't lie. The fact that you're an outlier doesn't change the situation.

I keep buying books - I guess I am just old fashioned.

Me too, though usually it's audiobooks for fiction and certain types of non-fiction. Being able to "read" a book while mowing the lawn, or whatever, has made chores far less annoying and opened up big blocks of time for reading.

Comment Re:Titan or Bust! (Score 2) 69

Venus's middle cloud layer is the most Earthlike place in the solar system apart from Earth**, is energy-abundant, has favourable orbital dynamics, easy entry, and the simple act of storing electricity for the night via reversible fuel cells - if plumbed in a cascade - can enrich deuterium (2 1/2 orders of magnitude more abundant on Venus), a natural export commodity, if launch costs are sufficiently low. The atmosphere contains CHONP, S, Cl, F, noble gases, and even small amounts of iron. Pretty much everything you need to build a floating habitat, which can be lofted by normal Earth air, aka people can live inside the envelope. Aka, unlike on Mars, where you live in a tiny tin can pressure vessel where any access to the outside tracks in toxic electrostatic dust and you waste away from low gravity, on Venus you'd be in a massive, brightly lit hanging garden, where you could live half a kilometer from a crewmate if they really got on your nerves.

Most Earthlike? Yes. Temperature, pressure, gravity, etc all similar. Natural radiation shielding equivalent to half a dozen meters or so of water over your head. Even storms seem to be of an Earthlike distribution. The "sulfuric acid" is overblown; it's a sparse vog, with visibility of several kilometers; with a face mask, you could probably stand outside in shirtsleeves, feeling an alien wind on your skin, only risking dermatitis if you stayed outside for too long.

Indeed, it'd actually be useful if the sulfuric vog was more common (to be fair, it's still unclear whether precipitation happens, and if so, whether rains or snows; the Vega data is disputed). Why? Because it's your main source of hydrogen. Highly hygroscopic and easily electrostatically attracted, so readily scrubbed through your propulsion system. First releases free water vapour when heated, then decomposes to more water plus SO3, and if you want you can further decompose the SO3 over a vanadium pentoxide catalyst to O2 + SO2, or you can reinject it into the scrubber as a conditioning agent to seed more water vapour. Of course, if precipitation happens, collection possibilities are basically limitless.

The surface is certainly hostile, but even 1960s Soviet technology was landing on it (also, contrary to popular myth, there is no acid at the surface; it's unstable at those temperatures, the sulfur inventory is only SO2 there). But in many ways, the surface is very gentle. Mars eats probes with its hard landings, but one Venera probe outright lost its parachute during descent and still landed intact, as the dense atmosphere slows one's fall. It's been calculated that with the right trajectory, a simple hollow titanium sphere launched from Earth could arrive at Venus, enter, descend and land all intact. Simple thermal inertia (insulation + a phase change material) can keep an object cool for a couple hours; with heat pumps, indefinitely (and yes, heat pumps and power sources for the surface conditions have been designed). Even humans could walk there with insulated hard suits, like atmospheric diving suits. Indeed, some of the first space suits NASA designed for the moon (ultimately ditched for weight reasons, despite the superior mobility performance) were similarly jointed hard-shell suits.

On Venus's surface, a lander or explorer can literally fly, via a compressible metal bellows balloon. Small wings / fins can allow for long glide ratios. Loose surface material can be dredged rather than requiring physical excavation, potentially with the same fan used for propulsion. Reversible ascent back to altitude can be done with phase change balloons - that is, at altitude, a lifting gas condenses and is collected in a valved container, and the craft can descend; at the surface, when one desires to rise, the valve is opened and the gas re-lofts the lander.

On Mars, you're stuck in one location. The problem is that all minerals aren't found in the same spot; different processes concentrate different minerals. And you can't exactly just get on a train to some other spot on the planet; long-distance travel requires rockets, and all their consumables. But on Venus the atmosphere superrotates every several days (rate depending on altitude and latitude), while latitude shifts in a floating habitat or lander can be done with minimal motor requirements. So vast swaths of the planet are available to you. Furthermore, Venus is far more dramatic in terms of natural enrichment processes; wide ranges of minerals are sublimated or eaten out of rocks and then recondensed elsewhere. Temperatures and pressures vary greatly between the highlands and lowlands as well. There even appear to be outright semiconductor frosts on parts of the planet. Lava flows show signs of long cooling times, which promotes fractionalization and pegmatites. Volcanism is common, primarily basaltic but also potentially secondary rhyolitic sources. A variety of unusual flows with no earth analogies (or only rare ones) show signs of existing, including the longest "river" channel in the solar system (Baltis Vallis). While there's no global tectonic activity, there appear to be areas of intense local buckling between microplates. The surface conditions of the planet also appear to have been very different at many times in the past. It's all a perfect setup for having diverse mineral enrichment processes. Yet there's almost no overburden (unlike Mars, which is covered in thick overburden on most of the planet).

As mentioned before, Venus has significantly superior orbital dynamics to Mars, due to the Oberth effect. Venus-Mars transfers are almost as fast and almost as low energy as Earth-Mars transfers. Venus-Earth transits are super-fast, esp. with extra delta-V added. The asteroid belt is, contrary to intuition, much more accessible from Venus than from Mars. Also, gravity assists are much more common around Venus - when we want to launch probes to the outer solar system, we generally start with sending them first inwards toward Venus, then back between Venus and Earth and outwards from there.

From a long term perspective, both Venus and Mars have problems with terraforming, with some things you can do "relatively easy", and some that require megascale engineering on scales best left to fantasy. You can boil off Mars's polar caps, but the amount of CO2 there is still quite limited, and there's just not that much nitrogen inventory on the planet (it's been lost to space), which also matters to plant cultivation. You could probably engineer active radiation shielding from orbit, maybe direct more light to the surface, but you can't increase the gravity. Etc.

With Venus, one of the earliest ideas for terraforming it was from Carl Sagan, before the planet was known well; he proposed seeding it with engineered bacteria to convert CO2 to graphite and release oxygen. He later rejected his idea, on the grounds that a high temperature surface of graphite and oxygen would be a bomb. Later studies showed that the timescales for said conversion would be tens of thousands to millions of years. But in a way, that is actually a savior to his idea, in that Venus's rocks contain unoxidized minerals. In analogy to the Great Oxygen Catastrophe on Earth that created our banded iron formations, slowly exposed to oxygen, Venus's rocks would weather and sequester the oxygen and deposited carbon. Hot, high-pressure high-oxygen conditions would never have a chance to exist.

Various faster methods have been proposed. A common one is that of the soletta, a thin orbital sunshade. Another is building an "alternative surface", aka propagating floating colonies to the point that they are the new surface - and indeed, below that surface, they could exclude sunlight to the below atmosphere. Regardless of the method, the cooler the atmosphere gets, the lower its pressure gets, to the point that you can start outright precipitating out the atmosphere out as icecaps.

Just like Mars will never have high gravity and probably never much nitrogen, Venus would probably never be fully Earthlike. It would have enough nitrogen that, barring loss to weathering, people would have a constant mild nitrogen narcosis, like always being ever so slightly tipsy. It would remain a desert planet, barring massive influxes of ice (which present their own challenges and problems), or of hydrogen (pre-cooling). But then again, the very concept of terraforming anything has always required one to put on thick rose-coloured glasses ;)

I don't say all this to diss on Mars. But our obsession with "surface conditions" has led us to ignore the fact that if you're going to the extremes of engineering an off-world habitat, having it be airborne is not that radical of an additional ask, esp. on a planet with such a big "fluffy" atmosphere as Venus. If Venus's atmosphere stopped at its Earthlike middle cloud layer, if there was a surface there, nobody would be talking about long-term habitation on Mars - the focus would have been entirely Venus. But we can still have habitats there. The habitat can, in whole or part, even potentially be its own reentry vehicle (ballute reentry), and certainly at least inflate and descend as a ballute (with a small supply of Earth-provided helium as a temporary lifting gas until an Earthlike atmosphere can be produced). Unlike with Mars entry, you're never going to be "off course", or "crash into something" because you got the location or altitude wrong.

(Getting back to orbit is certainly challenging from Venus - all that gravity that's good for your body has its downsides - but the TL/DR is, hybrid and/or air-augmented nuclear thermal rockets look by far to be the best option. Far less hydrogen needed than chemical rockets, far lighter relative to their deliverable payload, only a single stage needed, and in some designs have the ability to hover without consuming fuel. This is, of course, of great benefit for docking with a habitat, avoiding the need for descending rocket stages to deploy balloons and then to dock those to the habitat. The hydrogen and mass budgets involved are totally viable)

Comment Of course they don't: nobody READS books (Score 1) 154

Ofc I don't mean LITERALLY nobody. There are niches of readers here and there.

But my kids are all in their 20s and 30s, and they have many friends who say things like "you know, I haven't read a single actual book since college".

To me it's incomprehensible, and I sort of take it as evidence of the collapse but...is it really all that different than say, the 1950s? 1930s? Sure, intellectuals of all eras read but I don't believe the % of intellectuals by nature has particularly swung one way or another since then.

Comment Re:Lack of options (Score 1) 154

I agree. Some of it, I suspect, is that I've just read so many books now that I'm in 50s that when I read a trope-driven genre novel (SF, Fantasy, Mystery, Thriller, whatever), I rapidly feel like I've read this story before. I've gotten to the same place with TV and movies. Both mediums really suffer from a lack of any kind of originality, or even attempts at quirkiness. It all just feels like Thomas Kinked-esque cookie cutter.

I've started reading a lot more non-fiction, mainly history. Ironically, there's a lot more originality there than in most of the modern fiction I read.

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